Swear Bleep Detecting Eyebrows

November 10, 2016 by Jenny List 17 Comments

Swear on broadcast television and they’re going to bleep out the audio to protect the sensibilities of the general public. Swear bleeps are fairly standardised at 1kHz, or so [mechatronicsguy] tells us. You learn something new every day.

OK, it’s not as though there’s an ISO document somewhere detailing the exact tone to use when someone says a naughty word on camera, it is far more likely that a 1kHz tone is the most likely frequency to be at hand in a studio. It’s so ubiquitous that even audio engineers with nowhere near perfect pitch can identify it, and one to which an acquaintance of ours swears years of exposure have given his ears a selective notch filter.

Armed with this information, [mechatronicsguy] created a fun project. As a fan of the [electroBOOM] Youtube channel he made a set of LED eyebrows for a picture of his bleep-prone hero, and using a Teensy with its audio and FFT libraries he made them light up whenever a 1kHz tone is detected. It’s not the most amazing of hacks, but if you find yourself in need of a smile on a chilly November morning then maybe it’ll have the same effect on you as it did with us. He’s posted a quick video of the ‘brows in action which we’ve embedded below the break.

Continue reading “Swear Bleep Detecting Eyebrows” →

Retrotechtacular: [Walt] Builds A Family Fallout Shelter

November 9, 2016 by Jenny List 114 Comments

In the 1950s it seemed likely that the Cold War could at any minute take a turn for the worse, and we might all be consumed in the fiery conflagration of nuclear war. Fortunately neither the leaders on our side of the fence nor those on the other were the dangerous unpredictable lunatics their opponent’s propaganda might have portrayed them as, and instead we continued on our way uneasily gazing at each other over the Iron Curtain.

For civilian America, the Government created a series of promotional efforts to prepare them for the effects of nuclear war and equip them with the means to survive. Some of them like the infamous “Duck and cover” film seem quaint and woefully inadequate when viewed with several decades hindsight, but others tried hard to equip the 1950s American with what looked like the real means to survive.

Our film below the break today is part of one such effort. The Family Fallout Shelter was a booklet produced in 1959 by the Office of Civil and Defense Mobilization, and it described in detail the construction of a series of fallout shelters of differing designs. There was a concrete underground shelter, a partially buried twin-wall shelter with infill, and the one shown in the film, a basement fallout shelter made from concrete blocks. Our narrator and protagonist is [Walt], a capable bespectacled middle-aged man in a check shirt who takes us through the shelter’s construction.

We start with him giving some friends a tour of the finished shelter, and we see its cozy furnished interior with bunk beds and all mod cons. We’re told it would make a useful extra spare bedroom, or a darkroom. Then we flash back to construction as [Walt] takes us through all the steps required to build your own basement shelter. As he says, it’s a project that could be attempted by almost anyone, and what follows is a pretty good introduction to basic bricklaying. We can’t help being concerned about the security of those unmortared roof blocks in the face of a Tsar Bomba, but fortunately they were never put to the test. We do find it amusing that this is presented by the National Concrete Masonry Association — how better to boost sales than get the populace to build extra brick walls in every home?

The film and booklet provide a fascinating window into some of the culture surrounding preparations for nuclear war in the early Cold War era. The ideas that it would be survivable, and that two weeks in a home-made fallout shelter would be sufficient to ensure that civilians would be safe are in stark contrast to the then-secret deep shelters and long-term survival plans that the governments of the time created for themselves. It would be interesting to know how many of these home shelters were built, and how many survive. Did you ever spend a night in a basement spare bedroom with a blast wall?

We’ll leave you with the film’s closing words from the Director of the Office of Civil and Defense Mobilization.

“No home in America is modern without a family fallout shelter. This is the nuclear age.“

Continue reading “Retrotechtacular: [Walt] Builds A Family Fallout Shelter” →

A Pipe Organ For The MIDI Generation

November 9, 2016 by Jenny List 20 Comments

If you are a musician and you are also a Hackaday reader, there’s a good chance you’ll own at least one MIDI instrument. A synthesizer of some description, maybe a keyboard, or perhaps a drum machine. A pipe organ? Probably not.

If you answer to the name of [Wendell Kapustiak] though, you’d say yes to that question. He’s built himself a beautiful pipe organ from scratch, with hand-tuned wooden pipes, and for a modern touch he’s made it MIDI controlled. An Arduino Due sends its commands to a set of solenoid drivers, the solenoids then control the air flow from his wind chest through a set of plastic tubes to his organ pipes. Air supply comes from a shop vac in a sound-insulated box, with a pressure regulating chamber. The result is not perfect, he believes that the pipes are too close together and this somehow makes them difficult to tune, but to an outsider’s eye it’s a pretty impressive instrument.

[Wendell] is both a skilled and prolific maker, and his blog is rather a good read. The organ project is spread over a few years, so to get the full picture it is best to read his previous posts on the subject as well as the one first linked. He recounts his early experiments as well as giving us details of the electronics and the pipes. He’s put up a video showing the completed instrument which you can see below the break, and another more recently showing a recent one-LED-per-note modification.
Continue reading “A Pipe Organ For The MIDI Generation” →

When A CRT Isn’t Retro Enough: LEDs

November 8, 2016 by Jenny List 31 Comments

When we think of an old-style computer terminal, it has a CRT screen: either one of the big 1970s VDUs with integrated keyboard, or maybe one from a later decade with more svelte styling. You would have found other displays in use in previous decades though, and one of them came our way that we think it worthy of sharing.

[Dan Julio] was given several tubes of Siemens DL1416B 4-digit 17-segment LED displays by a friend, and decided to use them as an unusual retro display for his terminal project. These devices are an alphanumeric display with a parallel interface that can show a subset of the ASCII character set as well as a cursor. He had 213 of them, so made plans for a 64 character by 16 line display, however on discovering a quantity of the parts were non-functional he had to scale back to 12 lines of 48 characters.

The displays are mounted on PCBs in groups of four, controlled by a PIC16F1459 and some shift registers. These boards are then daisy-chained via a TTL serial line. The whole display shares one of the three serial ports on a Teensy 3.1 with his retro keyboard that has its own PIC controller, the others serving a serial printer port and the terminal serial port. The Teensy software has two modes: serial terminal or a Tiny Basic interpreter, and the relevant repositories are linked from the project page.

Since each set of DL1416Bs takes 250 mA, the whole display consumes about 9 A at 5 volts. On top of that the keyboard uses another 500 mA, so a sufficiently powerful supply had to be incorporated. This is mounted along with the Teensy in a very well-made enclosure, and the whole is mounted on what looks like a surplus monitor stand for a very professional finish.

To take us through the terminal’s features he’s posted a YouTube video that we’ve placed below the break. It comes across as a surprisingly usable machine, as he logs into a Raspberry Pi and edits a file, and takes us through some features of the BASIC interpreter.

Continue reading “When A CRT Isn’t Retro Enough: LEDs” →

A Vintage Interface For A Modern Radio

November 6, 2016 by Jenny List 10 Comments

The arrival of affordable software defined radio technologies over the last couple of decades has completely changed the way that radio amateurs and other radio enthusiasts approach the airwaves. There’s a minor problem with most software defined receivers though, being by their nature software driven they will usually rely on a host computer for their interface. Thus the experience is one of clicking mouse buttons or using keyboard shortcuts rather than the mechanical analogue dial interfaces that provided easy control of older radios.

This is a problem that has been addressed by [Jon Hudson, G4ABQ], with one of his SDRplay receivers. He’s mounted it and its control PC in the chassis of a very aged and non-functional Marconi CR100 communication receiver, and given it a control interface that only uses the Marconi’s front panel controls (YouTube link). A rotary encoder has been grafted onto the Marconi tuning capacitor with what looks like some Meccano, and in turn that feeds an Arduino which behaves as a keyboard for the benefit of the PC. Some extra buttons have been added for mode selection, spectrum zoom and shift, and care appears to have been taken to give their labels a period feel. Arduino code came courtesy of [Mike Ladd, KD2KOG]. The result is a very controllable SDR receiver, albeit one in a rather large case.

If you are interested in the project then we are told that it will be on the RS stand at Electronica in Munich next week, meanwhile we’ve put the video below the break.

Continue reading “A Vintage Interface For A Modern Radio” →

Turn That Old Tablet Into A Sub-$100 Linux Laptop

November 5, 2016 by Jenny List 43 Comments

Tiny laptops have always been devices that promise so much, yet fail somehow to deliver. From the Atari Portfolio palmtops through to the recent crop of netbooks they have been either eye-wateringly expensive if they are any good, or so compromised by their size constraints as to be next-to-useless. We’ve seen DOS, EPOC, Windows, WinCE, Palm OS, Linux distros and more in tiny form factors over the years, yet few have made a significant mark.

The prospect of a “proper” computer in your hand isn’t something to abandon just yet though. We are now reaching the point at which the previous generation of higher-end Android tablets are both acceptably powerful and sufficiently numerous as to be available at a very reasonable price. Perhaps these can provide the tiny laptop seeker with a basis for something useful. [NODE] certainly thinks so, because he’s produced a nice little Ubuntu laptop using a second-hand Nexus 7 tablet and a Bluetooth keyboard case. Android is replaced with an Ubuntu image, and a cardboard cut-out display bezel is held in place with magnetic strips. A step-by-step guide has been put up to help others interested in following the same path.

This is not the most amazing of hardware hacks, in that it involves mostly off-the-shelf items and a piece of software. However it’s worth a look because it does provide a route to a very acceptable little Linux laptop for an extremely reasonable price. One concern is that the Ubuntu version seems not to be a recent one, however we’re sure readers will point at any newer distribution builds in the comments. If you fancy a look at the finished laptop he’s posted a video which we’ve included below the break.

Continue reading “Turn That Old Tablet Into A Sub-$100 Linux Laptop” →

Brazing Aluminum

November 4, 2016 by Jenny List 80 Comments

Where do you stand on one of the eternal questions of metalwork: brazing, or welding? As your Hackaday writer, and the daughter of a blacksmith, it’s very much on the welding side here. Brazed joints can come apart too easily, which is why in the territory this is being written in at least, they are not permitted for the yearly vehicle roadworthiness test. If you’ve ever had to remove a brazed-on patch with an angle grinder, you’ll know which one you’d trust in a crisis.

What if the metal in question is aluminum? [George Graves] sends us a link to a forum discussion on the subject from a few years ago, and to a YouTube video which we’ve embedded below the break. Miracle brazing rods claim astounding toughness, but the world divides into those who favour TIG’s strength versus those who point to brazing’s penetration far between the surfaces of the metal to be joined. Having experimented with them a while back, we’ll admit that it’s true that aluminum brazing rods join broken parts impressively well. But yet again you won’t see this Hackaday writer riding a bike that wasn’t welded with the trusty TIG torch.

Take a look at the video, and see what you think. Even if it’s not a joint you’d stake your life on it’s still a technique that’s a useful addition to your workshop arsenal.

Continue reading “Brazing Aluminum” →